Good+math+web+sites

**Useful math web sites...**
[|The MacTutor History of Mathematics Archive at St. Andrew's University]

[|MathWorld - the best math resource on the web]

[|GeoGebra - open-source geometry and algebra software]

**Interesting but not necessarily useful math web sites...**
[|Clay Mathematics Institute's Millennium Prize Problems - seven of the hardest unsolved math problems with a $1 million prize for each]

[|Goldbach's Conjecture - my all-time favorite unsolved math problem]

[|Prof. Bob Devaney's Dynamical Systems and Technology Project site - lots of great fractal geometry here]

[|Non-Euclid - a hyperbolic geometry java applet]

[|Yturralde - Spanish artist/mathematician]

[|Nathan Sawaya - artist who uses Legos for his art medium. Not exactly math but very cool!]

**Completely useless but very interesting web sites - math songs for your amusement...**
[|The quadratic formula song by Michael Kelley]

[|Tom Lehrer's Derivative song]

[|Tom Lehrer's Delta for every Epsilon song]

[|Tom Lehrer's Lobachevsky song]

[|"I Will Derive!" video - parody song of "I Will Survive" by Gloria Gaynor]